What is Marfan syndrome?

Marfan syndrome is a genetic disorder that affects the body's connective tissue. Connective tissue holds the body's cells, organs, and other tissue together. Connective tissue is also important in growth and development.

What causes Marfan syndrome?

Marfan syndrome is caused by an abnormal gene. The affected gene is FBN1. It helps make a protein in connective tissue called fibrillin. The abnormal gene happens as follows:

In about 3 out of 4 cases, the gene is inherited from a parent who is affected. Each child of an affected parent has a 50% chance of having the disorder (autosomal dominant inheritance).

In about 1 out of 4 cases, the abnormal gene is from a new mutation. It is not inherited from a parent. Researchers believe this happens more often when the father is older than 45. The child also has a 50% risk of passing on the gene.

Marfan syndrome occurs about equally in boys and girls. It also occurs in all races and ethnic groups.

Who is at risk for Marfan syndrome?

A child is more likely to have Marfan syndrome if he or she has a parent with the disorder.

What are the symptoms of Marfan syndrome?

A child with Marfan syndrome can have many different signs and symptoms. The syndrome can affect the heart and blood vessels, bones and joints, and eyes. Symptoms can occur a bit differently in each child. They can include:

Abnormal facial appearance

Eye problems such as nearsightedness

Crowding of teeth

Tall, thin body

Abnormally shaped chest

Long arms, legs, and fingers

Curved spine

Flat feet

Poor healing of wounds or scars on the skin

The symptoms of Marfan syndrome can be like other health conditions. Make sure your child sees his or her healthcare provider for a diagnosis.

How is Marfan syndrome diagnosed?

The healthcare provider will ask about your child's symptoms and health history. He or she will give your child a physical exam. The health care provider will ask about any family history of Marfan syndrome. To be diagnosed with Marfan syndrome, your child must have some specific health problems affecting the heart, blood vessels, bones, and eyes.

Your child may also have tests, such as:

Electrocardiography (ECG). A test that records the electrical activity of the heart. It shows abnormal rhythms (arrhythmias).

Echocardiography. An exam of the heart that uses sound waves. It creates moving pictures of the heart.

Dilated eye exam. A complete eye exam that includes the inside of the eye.

CT or MRI scans. Imaging tests that check for abnormal bones or joints.